O Optics (Latin) Dan Mills Athens Technical College, Athens, GA, USA Beginning with Plato’ s Timaeus, philosophical treatises on optics from the ancienty world through the late middle ages and early modern period addressed optics through a religious and spiritual perspective. Many medieval philoso- phers on optics, including Abu Yusuf Ya‘qub ibn Ishaq Al-Kindi, Hasan ibn al-Haytham (Latinized as Alhazen or Alhacen), Roger Bacon, Witelo, and Robert Grosseteste were theologians as well as natural philosophers, and their discussions of optics all have varying degrees of religious impli- cations. Al-Kindi and Alhazen established the foundation upon which optical theory in the medi- eval Latin West would base optical theory through translations of the ancient sources into Latin as well as Latin versions of their Arabic sources. Latin sources on optics had their beginning with the Latin translation of and commentary on Plato’ s Timaeus by Chalcidius. Other important sources include Latin translations of Euclid, Ptol- emy, and Aristotle’ s psychological texts, De anima, De sensu and De memoria, as well as Seneca’ s Naturales quaestiones and Pliny’ s Naturalis historia. Latin translations of Galen’ s De aspectibus by Arabic philosopher Alhazen had a major influence on Roger Bacon’ s work on optics in his Opus Majus, “Optical Science” (De Scientia Perspectiva). The Polish natural phi- losopher Witelo, a contemporary of Bacon, wrote a text entitled Perspectiva, which appeared in Opticae thesaurus Alhazeni Arabis libri septem, and this text was the primary authority on optics until the seventeenth century. All of these texts analyzed optics through a phenomenological analysis of the nature of vision and perception and the connection vision and perspective have with psychology and the divine. Darrigol (2012) points out that Euclid’ s Optica was the first text on optics to receive attention from Arab philosophers, beginning with the ninth century consolidation by Arab philosopher Ibn Ishak al-Kindi. The Latin translation of al-Kindi’ s text, entitled De aspectibus, appeared in the twelfth century. Translations of Euclid’ s texts into Latin include De speculis and transla- tions of his Optica under the title De visu, as well as the pseudo-Euclidian compilation entitled De speculis based on Euclid’ s theories. A translation from Arabic into Latin of Ptolemy’ s Optica/De aspectibus also appeared in the twelfth century, as did an Arabic-to-Latin translation of Tideus’ De speculis/De speculis comburentibus/De aspectibus. Alhazen’ s Kitab al-Manazir was translated into Latin as De aspectibus/Perspectiva in the twelfth century as well, although scholars have yet to agree on the identity of the translator. For a more complete account of texts on optics translated into Latin, see Lindberg, pp. 209–213. Scholars of ancient, medieval, and early mod- ern optics differ on the relevance of psychology in # Springer-Verlag GmbH Germany, part of Springer Nature 2019 D. A. Leeming (ed.), Encyclopedia of Psychology and Religion, https://doi.org/10.1007/978-3-642-27771-9_200148-1